Scale Effects on Scale Tests of Crown Walls

Evaluation of scale effects in lab tests are one of the topics of interest for breakwater designers. In this case, the study is focused on rubble mound breakwater crown walls. The case structure selected was the crown wall in the top of the Principe de Asturias breakwater, Port of Gijon (Spain). Three tests were carried out on this breakwater cross section with different scales: field measurements at the prototype breakwater (scale 1:1), lab tests at 1:18.4 and 1:90 scales. The wave-induced horizontal forces from the three data sets were compared and differences were found. Force distributions were non-dimensionalized with wave distributions showing that no differences were noticeable between the lab tests while an 18% of smaller forces were measured at the prototype.